Families being supportive together: A multimethod and multi-informant intensive longitudinal study of family protective mechanisms for adolescent depression.

To advance the design and use of intensive longitudinal methods in investigations of adolescent depression, we conducted a multimethod and multi-informant study of daily parent-youth interactions, specifically, supportive communication, consisting of (a) naturalistic video observations of parent-youth interactions; (b) passive collection of Bluetooth Low Energy signals to approximate parent-youth proximity; and (c) scheduled, proximity-contingent and self-initiated ecological momentary assessments (EMA). We examined whether these novel and complementary approaches enhanced the assessment of parent-youth interactions, a key source of risk and protection for youth mental health. Specifically, we report participant compliance on the video recording procedures and describe preliminary results from our observational coding of supportive communication. We also report compliance rates on EMAs and examine the frequencies of parent-youth interactions per self-report and Bluetooth Low Energy signals. Participants in the 2-week-long protocol were 12- to 15-year-old adolescents (N = 138; 63.8% female, 42% Center for Epidemiologic Studies Depression ≥ 16) and their parents (95.7% biological mothers, 25% Center for Epidemiologic Studies Depression ≥ 16). Dyads completed mean 122.6 min (SD = 85.6) of video recordings. In 387 min of recordings from three pilot families, we identified 52 supportive communication episodes. The average parent and youth were compliant with EMA procedures, completing the recommended minimum of 40 cumulative surveys each. Parents and youth reported that they interacted with the other member in mean 56%-83% of the EMAs. The study demonstrates innovative ways to leverage technology to conduct multimethod and multi-informant intensive longitudinal assessments of interpersonal interactions, a key source of risk and protection for adolescent mental health. (PsycInfo Database Record (c) 2025 APA, all rights reserved).